MIT Physics Demo -- Centrifugal versus Centripetal Motion

[swenbuddy1]

thanks MIT, we can always count on you to further our knowledge. this video is proof that your university is the best

[thesickandwounded]

well this was pointless and useless.

[ohitsmeoh]

They're trying to demonstrate rotation is actually applied in a straight line. Centrifugal and centripetal forces are equal while the ball is traveling in a circle.

[dukes362]

you could have colored the ball with a bright colour to increase its visibility

[CHEESYhairyGASH]

you stupid bunch of cunts

[Oshyrath]

@CHEESYhairyGASH you're not funny. just stupid

[CHEESYhairyGASH]

@Oshyrath thanks

[platypusone]

Woah! Nice catch there wild man!

[flyingjazz]

If you want to talk about centrifugal force then mount your video camera on the wheel.

[NickManor]

@flyingjazz He wrote "in the rotating frame of reference"

[fredb3]

What has this taught the student.

Well as we can see he certainly learned that gravity has an effect on the ball.

My proof!

Study the first time the ball is launched, the student overlooks the effect of gravity and observes the ball fall, without trying to catch it

After the student has observed the trajectory of the ball based on it's speed / trajectory vs gravity he can therefore acccuratly predict where the ball will go and as a result catches it.

Science at work here folks

xD

[fredb3]

@fredb3

Degree level at that xD

[staphinfection]

Maybe in your next MIT demo, you can explain how white lab coats make you appear smarter than you really are.

[quidproquo2004]

@staphinfection Maybe the problem is your inferiority complex?

[dannyreijo]

Yeah it's not a force, its a property of bodies to continue in their initial direction.

[bradivoy]

@dannyreijo ... which produces the force opposing the one that tries to change that direction.

[dannyreijo]

The Phrase Centrifugal acceleration should not exits...Newtons 1st Law is correct. ITS NOT A FORCE PULLING THE BALL OF THE WHEEL!!!

[jimmayl1]

Well, its a virtual force. It depends on your frame of reference. Say you're in a car turning a tight corner. In the frame of the car, you appear to feel a force outwards, but in the static frame the car feels a force inwards and essentially hits you.

I know you get it, just thought I'd point it out for others :P

[imbrd]

haha ad fun

[thefencejumperengine]

I have a simple question that I hope someone can answer. When the ball is released from the rotating disc, does any type of recoil appear or is conservation at place???

[wiimaster98]

It seems to me that since the ball leaves with its tangential velocity and that we must take conservation in terms of this and that the cord holding the ball had mass, I feel as though the cord moved with minimal velocity and accelerated down due to gravity.

[wowsa0]

While the ball is spinning at a constant angular velocity, the axle must exert a centripetal force on the ball to keep it in place. When the ball is released, this force vanishes. That is the only thing that resembles "recoil". No force is applied to the ball to release it, rather a force preventing it from flying off is taken away.

[thefencejumperengine]

Thanks, preciate you time taken.

[jayls5]

@thefencejumperengine

I imagine you can test this yourself. If you've ever swung a ball (or any weight) on a string when you were little and it let go, you can probably remember what happened. :)

[Kirkdabossplaya]

Centrifrugal may have dome applications somewhere. But I cant be arsed to get the books out and have a look see. Some of these MIT videos are excellent and I wil use the centre of mass ones for my GCSE students. So thanks for posting.

[Kirkdabossplaya]

Do any of you ot even know what the fuck your talking about? No such thing as centripetal acceleration? What keeps satellites in geo-sync orbit? angular velocity and a centripetal force *called gravity) In classical mechanics what keeps electrons in orbit? (centripetal force (electrostatic in this case) Centrifrugal is dependant upon the frame of reference you are observing. So classically it does not exist. Because we live in a classical macroscopic society.

[syberraith]

I love MIT and I feel lucky in a good way to have access to these videos.

After watching this particular one, I think I finally understand the centripetal vs centrifugal forces.

In short, centrifugal force is simply inertia. :)

[m1ndcontroller]

There is NO SUCH FORCE AS CENTRIPETAL!!!

The force holding the ball comes from molecular cohesiveness between the particles of the string!!!!! Angular momentum is completely irrelevant!!!

This is more bogus establishment propaganda; claiming that there are discreet forces where none exist!!

[happysceptic]

You'll be telling us next that there is no such thing as centrifugal force. *Yawn*. The ALLCAPS and excalmation marks really help your argument, although I wasn't sure whether to rail against establishment lies or lies from a made-up establishment. Well done anyway - here's a pound.

[TinselKoala]

Centrifugal (center-fleeing) is fictitious and centripetal (center-seeking) is real, but this choice depends on reference frame. In the stationary frame the ball goes off tangentially and the centrifugal force is clearly fictitious. Sitting on the disk looking at the ball, it appears to move directly away at first, giving the illusion of a center-fleeing acceleration--the effect of the false centrifugal force. The centripetal force is quite real--it is what keeps the ball moving in a circle.

[jccalmeiro]

Centrifugal force is not tangencial. It is simetric to centripetal force. If the centrifugal was tangencial, then the ball would never go tangencial when you cut the string..

[iplop]

So would I be correct in saying that the centripetal force is the force being exerted on the string (between the center of rotation and the ball) and the the centrifugal force is the tendency of the ball to leave it's orbit on a tangential line?

Great video by the way. I had always seen these two terms as synonymous.

[Adrianrff]

It all comes down (alwas) to Newton's first and second. The ball will always "want" to stay moving with constant velocity (constant speed AND direction), so unless there's some force that accelerates it (so it changes it's direction) it will go off tangencially, what keeps the ball in circle is the centripetal force (that's why it's called the real one), the centrifugal force is a relative acceleration F = mxa (not a real force) that's the one that seems push you to the side of a car in a curve

[Adrianrff]

The centripetal in this case would be the tension in the string, which when eliminated allowed the ball to do what it always wants to do (Nwt 1st): move in a straight line with the speed it had

[marsCubed]

nice catch at the end.

[marioalonso0304]

second comment. yo trabajo en esto para inventar mi impulsor inercial

[JasoniumGH]

first comment! i love this channel